Filter mask facelet



April 25, 1967 A. BLOOM ETAL FILTER MASK FACELET Filed Dec. 28, 1964United States Patent 3,315,674 FILTER MASK FACELET Aaron Bloom,Pasadena, and John D. Olt, Sierra Madre, Calif., assignors to SierraEngineering Company, Sierra Madre, Caiifl, a corporation of CaliforniaFiled Dec. 28, 1964, Ser. No. 421,435 3 Claims. (Cl. 128l46.4)

The invention relates to breathing masks, such for example as those wornby the crewmen of aircraft and is especially related to the provision ofsanitary means to avoid contamination of one crewman by the respiratoryailment which another crewman might be afiiicted with.

In the handling of high-flying airplanes the cabin and cockpit arecustomarily pressurized so that the crewmen of the airplane do nothabitually wear breathing masks on their faces. As a necessaryprecaution however, a suitable breathing mask is supplied for eachindividual crewman, which may either hang on the crewmans neck, orpursuant to more recent regulations may be suspended from the interiorof the cockpit so that it can be quickly grabbed and donned should therebe a failure of cabin pressure for any reason.

On those occasions particularly where the mask may be suspended in thecockpit there is no reason to change masks everytime the crew changesbecause with adjustable harness the mask for one crewman may be readilyreadjusted to fit a succeeding crewman in the change of crew wherefacial characteristics differ.

It is however, quite usual for crewmen to be afiiicted with head coldsor other respiratory ailments which is desirable not to pass from oneperson to another. Since also it is necessary each time a crewman whenhe takes his position in the cockpit to be certain that the mask at hisdisposal is carefully adjusted to his face he must don the mask uponarriving in the cockpit and make the adjustment. This of course is thesame mask which may previously have been donned and adjusted by thepreceding crewman who may have been afiiicted with a respiratoryailment.

Since the adjustment must be made while the oxygen supply is open to themask and the radio equipment is in place, these conditions must bemaintained irrespective of what sanitary device is employed to preventcontamination of the succeeding crewmen.

It is therefore among the objects of the invention to provide a new andimproved filter mask facelet which is capable of protecting each crewmanas he adjusts the mask to fit his face after the mask has previously:been used by another.

Another object of the invention is to provide a new and improved filtermask facelet which offers no objectionable resistance to the flow of airinto and out of the mask while it is in place and which also will notinterfere with operation of the conventional breathing valve ormicrophone fixture.

Still another object of the invention is to provide a new and improvedfilter mask facelet and mask combination wherein the facelet issubstantially self-sustaining both in place on the mask and prior toplacement in the mask so that it clears not only the nose and mouth ofthe wearer but also the breathing valve and microphone equipment.

Further included among the objects of the invention is to provide a newand improved filter mask facelet which is extremely light in weight,substantially pervious to offer no objectionable obstruction to the flowof air or gas, which can not damage in any way the breathing ormicrophone equipment in the mask and which is sufficiently inexpensiveto be freely disposable after each use.

The objects of the invention also include the provision of a filter maskfacelet which is sufiiciently firm so as to be capable of holding itselfin position on the face piece of the mask when not in use withoutemployment of auxiliary holding means.

With these and other objects in view, the invention consists in theconstruction, arrangement and combination of the various parts of thedevice, whereby the objects contemplated are attained, as hereinafterset forth, pointed out in the appended claims and illustrated in theaccompanying drawings.

In the drawings:

FIGURE 1 is a side elevational view of a mask assem bly including thefilter mask facelet in position on a crewman.

FIGURE 2 is a plan view of the filter mask facelet alone looking at theface contacting side thereof.

FIGURE 3 is a fragmentary longitudinal sectional view of the facecontacting portion of a typical face piece provided with the filter maskfacelet in position, taken for example, at the line 3-3 of FIGURE 2.

FIGURE 4 is a fragmentary cross-sectional view of the facelet materialdrawn to an enlarged scale.

In an embodiment of the invention which has been chosen for the purposeof illustration there is shown a mask assembly of substantiallyconventional form incorporating a formed face piece 10 having a rim 11to which is tied a relatively yieldable sealing bead 12. The

rim 11 has a shape and contour approximating the shape and contour ofthe face around the line of contact of the bead 12 with the face. Tomake certain of an appropriate seal the bead may be formed with aninside resilient mass 13 of material held in place by a flexible jacket14. Edges 15 and 16 of the flexible jacket are bound to the rim 11 andan out-turned portion 17 thereof by some appropriate conventionaladhesive.

To mount the face piece upon a head 18 of a crewman there may beprovided an ear piece 19 having a head strap 20 and a neck strap 21fastened respectively to the. top and bottom of the ear piece. A maskstrap 22 including an adjustable buckle 23 is fastened at one end to theear piece 19 and at the other end to the face piece 10. An oxygen supplyhose 25 is connected to a valve housing 26 on the face piece, the valvehousing being one containing a conventional breathing valve device. Alsomounted upon the face piece is a microphone fixture 27 to which a Wirelead 28 is connected so that a microphone (not shown) within the facepiece can be connected to the communication system.

A mask facelet is indicated generally by the reference character 36. Themask facelet is constructed of felted fibers which in final form can bemolded so as to be capable of retaining a selected shape andconfiguration such as that shown in FIGURES 2 and 3. The facelet may bedescribed as including a central portion 31 dished so as to provide achamber 32 large enough to accommodate the forward portion of the faceof the crewman. A narrow section 33 of the chamber 32 is sufficient toaccommodate the nose whereas the lower portion, being larger, issufficient to accommodate the mouth. Around the edge of the facelet 30is a large rounded rim 34 which has substantially a shape and contourcomplementary with respect to the bead 12. The rim 34 has a pocket 35extending through the entire perimeter the pocket 35 being open towardthe bead 12 to permit application of the rim 34 of the facelet over thebead. Throughout some portions of the perimeter the rim 34 extends notover but also around the bead so that the facelet is fastened to thebead with relative security sufficient so that it cannot be easilyknocked off when not in use.

It is important that the character of the material forming the facelet30 be sufiiciently pervious to the flow of 3 air or oxygen so that theresistance to fiow when the mask is in place on the face is virtuallynegligible.

To make certain of a facelet of satisfactory structural characteristicsthe material may be formed of multiple layers 36, 37, and 38 for exampleof relatievly long and somewhat resilient fibers of some appropriatesynthetic plastic resinous material or other satisfactory natural fiber.By felting the individual layers of long and extremely fine fiber thefibers of respectively adjacent layers can be laid in a somewhatcross-wise relationship one with respect to the other and so that theoutermost fibers of adjacent layers mingle with each other and interlockto a degree when the respective layers are pressed together to form acomposite sheet. Forming the sheet material in this fashion helpsprovide a degree of stiffness sufficiently so that the mask facelet,once molded into a form adapted to fit inside of the face plate, willhold the form as long as needed. This is of assistance not only in beingable to keep the facelet in position on the face piece when not in usebut also keeps keep the central portion 31 distended away from the noseand mouth. The construction described is also productive of a sheetmaterial so light and yielding that should the bowed area ofthe centralportion 31 be pushed into contact with one or another of the parts ofthe valve assembly in the valve housing 26 or the parts of themicrophone fixture 27 no damage will result to either.

Moreover by constructing the preformed facelet in the form and moreparticularly of the material suggested, the facelet can be constructedvery inexpensively sufficient so that each facelet in turn can bedisposed of after it has served one adjustment.

Normally the face piece will be provided with such a facelet in placeand thereby ready for immediate use for adjusting to the face of thecrewman. Should this not be feasible packages of appropriate faceletscan be stored conveniently and applied over the bead of the mask whenneeded. Moreover the material of the facelet is such that it need not beprecisely molded to fit each individual face piece. The rim 34 andpocket 35 of the facelet can be molded sufficiently around any one of anumber of different types of beads 12 and, the central portion 31maintained sufficiently clear of the face to accommodate many differenttypes of nose structure and different locations of microphone andbreathing valve apparatus within the face piece.

Having described the invention, what is claimed as new and in support ofLetters Patent is:

1. In a mask face piece for application to the face of a wearer in aposition covering the nose and mouth, a face fitting rim on the facepiece and a relatively yieldable sealing head on said rim for sealingengagement with the face when the mask is in position thereon, thecombination of a filter facelet comprising a sheet filter mediumcomprising multiple layers of separately felted fibers pervious to thepassage of air therethrough at negligible resistance, a rim on saidfacelet adapted to conform with the outline and contour of the sealingbead, said rim having a substantially continuous self-sustaining pockethaving a wall surrounding said sealing head, said facelet having anopening on one side, said facelet having a selfsustaining mid portionextending toward the open side of said pocket to positions clear of thewearers nose and mouth.

2, In a sanitary mask testing assembly comprising a formed face piecefor application to the face of a wearer in position covering the noseand mouth, a face fitting rim on the face piece and a relativelyyieldable sealing bead on said rim for sealing engagement with the facewhen the mask is in position thereon, breathing valve means at aforeward portion thereof and a microphone fixture adjacent said valvemeans, the combination of a filter facelet comprising a sheet filtermedium pervious to the passage of air therethrough at negligibleresistance, a rim on said facelet in conformance with the outline andcontour of said sealing head, said rim having a substantially continuouspocket therein with an opening on one side mounting the facelet inposition in the face piece, said facelet having a self-sustaining midportion extending toward the open side of said pocket to positions clearof the wearers nose and mouth and clear of the breathing valve andmicrophone.

3. In a sanitary mask testing assembly comprising a formed face piecefor application to the face of a wearer in position covering the noseand mouth, a face fitting rim on the face piece and a relativelyyieldable sealing bead on said rim for sealing engagement with the facewhen the mask is in position thereon, breathing valve means at aforeward portion of the face piece and a microphone fixture adjacentsaid valve means, the combination of a filter facelet comprising a sheetfilter medium having a thickness of from about 4, to 7 inch, said sheetcomprising relatively long semi-resilient fibers in multiple layers ofseparately felted fibers wherein surface fibers on respectively adjacentfaces of adjacent layers are intermingled and interlocked, said sheetbeing pervious to the passage of air therethrough at negligibleresistance, a rim on said facelet in conformance with the outline andcontour of said sealing head, said rim having a substantially continuouspocket therein with an opening on one side and with a wall surroundingapproximately half the exterior of the sealing bead whereby to retainthe facelet having a self-sustaining mid portion extending toward theopen side of said pocket to positions clear of the wearers nose andmouth and clear of the breathing valve and microphone.

References Cited by the Examiner UNITED STATES PATENTS 2,681,060 6/1954Swindell 128-146 2,997,550 8/1961 Traller 128-141.l 3,169,171 2/1965Wachs et al 179-185 3,220,409 11/1965 Liloia et al 128-146 RICHARD A.GAUDET, Primary Examiner. K. L. HOWELL, Assistant Examiner.

1. IN A MASK FACE PIECE FOR APPLICATION TO THE FACE OF A WEARER IN APOSITION COVERING THE NOSE AND MOUTH, A FACE FITTING RIM ON THE FACEPIECE AND A RELATIVELY YIELDABLE SEALING BEAD ON SAID RIM FOR SEALINGENGAGEMENT WITH THE FACE WHEN THE MASK IS IN POSITION THEREON, THECOMBINATION OF A FILTER FACELET COMPRISING A SHEET FILTER MEDIUMCOMPRISING MULTIPLE LAYERS OF SEPARATELY FELTED FIBERS PERVIOUS TO THEPASSAGE OF AIR THERETHROUGH AT NEGLIGIBLE RESISTANCE, A RIM ON SAIDFACELET ADAPTED TO CONFORM WITH THE OUTLINE AND CONTOUR OF THE SEALINGBEAD, SAID RIM HAVING A SUBSTANTIALLY CONTINUOUS SELF-SUSTAINING POCKETHAVING A WALL SURROUNDING SAID SEALING BEAD, SAID FACELET HAVING ANOPENING ON ONE SIDE, SAID FACELET HAVING A SELFSUSTAINING MID PORTIONEXTENDING TOWARD THE OPEN SIDE OF SAID POCKET TO POSITIONS CLEAR OF THEWEARER''S NOSE AND MOUTH.